Device for truing grindstones



2 Sheets-Sheet 1.

(No Model.)

M. A. BARBER;

DEVICE FOR TRUING GRINDSTONES.

Pa ented Sept. 9, 1884.

WlT NESSES, 2M $66M INVENTOR N. PC ERS. mo-Lilhogramr. wnmn m. n. c

2 Sheets-Sheet 2.

(No Model.)

M. A. BARBER. DEVICE FOR TRUING GRINDSTONES.

Patented Sept-9, 1884.

INVENTOR.

waTNEsEsfiM M N. PETERS. Phclo-Liihognphlr. Wash ngton. B46:

UNITED STATES PATENT @FFECF.

MICHAEL A. BARBER, OF NORWVICH, CONNECTICUT.

DEVICE FOR TRUING GRINDS TONES.

SPECIFICATION forming part of Letters Patent No. 304,774, dated September 9, 1884.

Application filed April 12. 1884. (No model.)

method of hanging and running a pair of grindstones, my immediate obj ectbeing to cause said stones to automatically level the outcrsurface or periphery ofeach other and to keep said surfaces always smooth and ready for use. Owing to the fact that all grindstones have spots harder or softer than the main body of the stone, they soon lose their original circular form, the hard spots protruding and becoming so prominent that it becomes necessary to turn off the periphery of the stone with tools specially prepared for the purpose. To keep a stone in condition to use, this turning-01f operation must be frequently resorted to. It is my purpose in this present invention, as before gtated, to furnish meansfor automatically truing up such stones. This I accomplish by so hanging two stones that their peripheries come in direct contact with each other as they revolve, one of said stones being so hung that it has no lateral or sidewise movement, the other stone being arrangedto rotate at a slightly slower or faster rate of speed, and also by means of peculiar mechanism, as hereinafter described, to traverse laterally back and forth across the face of its mate, to bring the peripheries of both to a parallel with the drivingarhers and at right angles with the sides of said stones. If one of the pair of stones were not arranged to traverse laterally, the hard spots in one stone would soon cut or turn grooves in the other, and the object sought after would not be attained.

In the accompanying drawings, Figure 1 isa side elevation of my device, a portion of the supporting frame or trough being cut away to show more clearly my method of adjusting horizontally the bearings which support the stones, so that as said stones become worn and reduced in diameter their peripheries may again be brought in cont-act with each other.

Fig. 2 is -a top or plan view of the same. Fi 3 is a vertical transverse section taken through the center of one of the stones, showing a convenient and inexpensive method of locking the adjustable bearings to the bed or trough. Fi 4 is a View, somewhat enlarged, of the gears, cam, spring, &c., employed to produce the traversing movement of stone B.

A represents a frame or trough as commonly constructed, having longitudinally-adjustable bearings a a, in which are hung the arbors which support the grindstones B C. By a sys tern of belting substantially as shown in Fig. 1 the stones are rotated in opposite directions, as indicated by the arrows 1 2. 1

The carriages which form the lower half of the arbor-bearings are so shapcdthat they lock under a projecting rim or flange, b, on the bed A, (see Fig. 3,) and are preferably connected by a cast-metal frame, E, which passes around the stone, reaching from the bearing on one side to its mate on the opposite side. By thus making thetwo bearings of each stone of practically one piece of metal I am able to adjust the arbor-bearings with a single screw, 0,

. at each end of the machine, said screw passing through the bed A and engaging a threaded lug, (Z, on frame E. Said adjusting-screw c has a convenient form of hand-wheel c on its outer end, and as said wheel is rotated the bearings a a travel inward or outward, as desired, a fine adjustment of the stones and bearings being thus obtained. The flange f pro vides a convenient tool-rest, and also serves to throw the waste water back again into the trough A.

To produce the desired traversing movement of stone B, I have provided the system of gears, &c., shown in Figs. 2 and 4. i is a gear fixed rigidly to the bearing a and having secured to its outer side a bracket, in which is pivoted a friction roll or pulley, h. Near pulley F, and fitting loosely on the arbor which carries F and B, is a gear, 70, having formed on its inner side a cam, m, which engages frictioirroll h, above referred to. Gears a 0 travel together aiid rotate on a stud fastened rigidly to one of the spokes of pulley F. -The gearsa, o, audt' may, if desired, be of the same size and number of teeth; but the loose gear k, which carries cam m, should have one or two teeth more or less o justable on said frame, one of said stones bethan gear 1. Gears n ando mustbe of the same size and number of teeth. As pulley F revolves, it carries with it n and 0, the fixed gear i causing them to rotate slowly, and they in turn causing loose pulley k and cam m to rotate. Now, it will be evident that if gears 'i and L" were of the same size and number of teeth, gear 70 would remain in a given position; but as it has one or two teeth less than gearz', it is caused to rotate very slowly, and as its cam engages roll h the arbor and stone are moved laterally until the outer point of the cam is reached, when the spring 8 draws or forces the stone and arbor back again. This sidewise movement is repeated at regular intervals, causing the stone B to traverse very slowly back and forth across the face of stone 0, reducing the high spots on both stones and keeping them perfectly round.

I am aware that a pair of grindstones with their peripheries in contact (but revolving continually in the same plane) have been used heretofore, and I do not therefore broadly claim such an arrangement of stones.

What I do claim as new, and wish to secure by Letters Patent, is-

1. In combination with a single supporting frame or trough, a pair of grindstones revolving in bearings which are longitudinally ading arranged to traverse laterally back and forth across the face of its mate for the purpose of leveling the peripheries of said stones, substantially as hereinbefore described.

2. In combination with a suitable supporting-frame, a pair of grindstones hunginbearings longitudinally adjustable on said frame, said bearings being formed with a downward projection or lug which hooks under flange b of the supporting-frame, the fixed gear 1', and friction-roll h, the gears 0 a rotating on a stud secured to a spoke of pulley F, the loose gear 75, cam m, and the retractor-spring s, said parts being so arranged and connected that a continuous lateral traversing movement is imparted to stone 13, substantially as and for the purpose specified.

3. In combination with a suitable supporting-frame and a duplex system of grindstones wherein one stone is arranged to travel laterally and continuously back and forth across the face of its mate, the bearings a a, having a cast-metal frame, E, extending from one bearing around the stone to the opposite bearing, and having means for longitudinal adjustment on frame A, as and for the purpose specified.

MICHAEL A. BARBER.

\Vitnesses:

FRANK H. ALLEN, EARL WARNER. 

